There are, of course, many ways to keep beverages cold ranging from simply packing the beverages in crushed ice to sophisticated coolers with temperature control features.
Examples of some patented devices in this field which are of relevance to the present invention include those disclosed in the following U.S. Pat. Nos. 415,980 to Sachs; 662,541 to Miskololzy; 2,648,954 to Wheeler et al; 2,979,227 to Norton et al; 4,295,345 to Atkinson; and 4,554,798 to D'Amour et al.
Briefly considering these patents, the D'Amour et al. patent discloses a bottle cooling device which is made of a plastic material filled with a refrigerant. The unit is frozen and placed on the necks of the bottles to be kept cool. The Norton et al patent discloses a container for keeping a six-pack of bottled beverages cold. Crushed ice is placed around the bottles in the container. The Atkinson patent discloses a cooling container for keeping cans cold including a top section having a slow warming cooling gel contained therein. The Wheeler et al patent discloses a refrigerated carton including circular compartments. Dry ice is placed in the partitions between the compartments. The Sachs patent discloses a portable cooler for drinking glasses including cone-shaped partitions for receiving the bottles to be cooled. The Miskoloczy patent discloses a frozen container for keeping beverages cold.
A continuing problem with simple devices for providing cooling of beverages, i.e., those that use ice, is that the ice melts relatively rapidly particularly when in cubed or crushed form. Further, cooling devices which require a separate permanent container for the ice tend to be relatively expensive and impractical for some uses. For example, the cost of such devices would preclude a grocery store or convenience store from giving the device away to customers for use in cooling beverages purchased at the store.